弹性搜索：如何提取与查询短语/字符串匹配的所有“字段名称”

Question

我想提取搜索文本出现在弹性搜索（存储）索引文档中的字段名称。

在弹性搜索中是否可以进行这种类型的查询，我在 C# 中使用 Nest Client

请参考以下示例：

示例：员工文档 { "first_name" : "emp first", "last_name" : "emp last" }

输入搜索文本：“first” 预期结果：["first_name"]

输入搜索文本：“emp” 预期输出：["first_name", "last_name"]

谢谢， AT

Answer 1

elasticsearch 中有一个特性"Named Queries"，可以为每个查询命名，elasticsearch 会返回匹配的查询名称

对于您的情况，您可以使用此查询

GET index/doc_type/_search
{
  "_source": [
    "first_name",
    "last_name"
  ],
  "query": {
    "bool": {
      "should": [
        {
          "match": {
            "first_name": {
              "query": "emp",
              "_name": "first_name"
            }
          }
        },
        {
          "match": {
            "last_name": {
              "query": "emp",
              "_name": "last_name"
            }
          }
        }
      ]
    }
  }
}

Elasticsearch 会返回这样的结果

{
  "took": 90,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 16.399673,
    "hits": [
      {
        "_index": "index",
        "_type": "doc_type",
        "_id": "1",
        "_score": 16.399673,
        "_routing": "1",
        "_source": {
          "first_name": "emp first",
          "last_name": "emp last"
        },
        "matched_queries": [
          "first_name",
          "last_name"
        ]
      }
    ]
  }
}

你也可以用highlighting做同样的事情

GET index/doc_type/_search
{
  "_source": [
    "first_name",
    "last_name"
  ],
  "query": {
    "bool": {
      "should": [
        {
          "match": {
            "first_name": "emp"
          }
        },
        {
          "match": {
            "last_name": "emp"
          }
        }
      ]
    }
  },
  "highlight": {
    "fields": {
      "first_name": {},
      "last_name" : {}
    }
  }
}

示例响应：

{
  "took": 90,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 16.399673,
    "hits": [
      {
        "_index": "index",
        "_type": "doc_type",
        "_id": "1",
        "_score": 16.399673,
        "_routing": "1",
        "_source": {
          "first_name": "emp first",
          "last_name": "emp last"
        },
        "highlight": [
          "first_name" : ["<em>emp</em> first"],
          "last_name" : ["<em>emp</em> last"]
        ]
      }
    ]
  }
}